The coating agents containing a metal alkoxide such as tetraethoxysilane (TEOS) and an aminosilane compound have been known from long ago. Such coating agents, however, were poor in film forming properties and had difficulties in making a film. Also, the film strength (hardness) provided by use of such coating agents would prove unsatisfactory for certain applications.
For instance, Patent Document 1 describes a coating resin composition comprising a metal alkoxide such as tetraethoxysialne (TEOS) or its condensate and an aminosilane compound. Although use of such a metal alkoxide condensation product could provide an improvement of film forming properties, there still was room for improvement of hardness of the obtained film. Patent Document 1: JP-A-8-295826